We are studying the effect of various psychosocial factors on host resistance to malignant melanoma. A detailed characterization of these factors in patients with melanoma, Clinical Stages I and II, is being obtained. In addition certain endocrine and immune parameters are also being studied. We are testing several hypotheses which may distinguish those patients suffering recurrence of their disease from others who either remain disease-free or have a delayed recurrence. At one year, significant correlations with disease-free status in 31 patients were found with (1) number of positive lymph nodes, (2) ABO type, and (3) melanoma adjustment self-rating score (see text). A subsequent group of 33 patients studied confirmed that the number of nodes and the melanoma adjustment score correlated with the one year disease status. Thus it would appear that a psychological variable, the melanoma adjustment score is of major importance in predicting relapse.